A Kingdom Hearts fan species created by Sachasketchy, the light element equivalent to the heartless.

From his page on furaffinity: https://www.furaffinity.net/view/56286517/

The other day in the Patreon exclusive part of the Discord. I was wondering in Kingdom Hearts, if light and darkness are supposed to be equal, what happens if a heart succumbs to the light?

We wound up with these. The Lucem. Some are definitely born naturally and usually passive but hostile versions can be born within people due to over indulgence. Too much of a good thing. When a Lucem forms the heart and body merge into 1 and warp the being into a mischievous creature that runs on pure dopamine. The hive mind of the Lucem only want to do one thing, make more Lucem and they'll turn anyone and everyone they can.

"What is the danger of overwhelming light? You can't have the good without the bad. If too much light snuffs out the darkness, then no new light can be formed. No new worlds can be created, all would be come 1 and stagnant and eventually life would cease to exist. Balance should be maintained in order for all to exist." (Probably some sh*t Xehanort's Ghost would say...)